Android中UDP发送报文

落日映苍穹つ 2021-11-05 18:30 300阅读 0赞

###  实现代码 上面写了备注 ###

//随机的uuid
            String uuid = UUID.randomUUID().toString();
            //定义传输的数据 userName是我接收的参数
            final String s = "TEL=" + username + "&SEQ=" + uuid;
            //key是我后端的协商秘钥
            String key = "";
            //aes加密 这里有个aes的工具类
            final AES aes = new AES(key);
            byte[] enContentSend = aes.encrypt(s, key);
            assert enContentSend != null;
            final ByteBuffer bf = ByteBuffer.allocate(4 + enContentSend.length);
            bf.putInt(enContentSend.length);
            bf.put(enContentSend);
            bf.position(0);
            logger.info("将字符串长度转换为byte" + Arrays.toString(bf.array()));
            //设置ip地址
            final String hostIP = "192.168.7.1";
            //设置端口地址
            final int port = 8080;
            new Thread(new Runnable() {
                @Override
                public void run() {
                    DatagramSocket socket = null;
                    try {
                        socket = new DatagramSocket();
                        socket.setSoTimeout(3_000);
                        // 2、创建host的地址包装实例
                        SocketAddress socketAddr = new InetSocketAddress(hostIP, port);
                        DatagramPacket out = new DatagramPacket(bf.array(), bf.capacity(), socketAddr);
                        socket.send(out);
                        byte[] buffer = new byte[1024];
                        DatagramPacket packet = new DatagramPacket(buffer, buffer.length);
                        socket.receive(packet);
                        enContentReceive = AES.byte2hex(packet.getData()).substring(0, 136);
                        logger.error("收到加密密文(带数据长度)：" + enContentReceive);
                        String enContentRec = enContentReceive.substring(8);
                        logger.error("收到加密密文(纯加密数据)：" + enContentRec);
                        enContentRec = enContentRec.substring(0, 32);
                         //使用秘钥解密
                        String deContent = aes.decrypt(enContentRec, "0123456789012345");
                        logger.error("加密的数据" + enContentRec + "解密的数据" + deContent);
                        //93119462813
                        //成功和失败的结果处理 具体的按后台返回处理
                        if (deContent != null && deContent.equals("RESULT=ERROR")) {
    
                            
                        }
                        if (deContent != null && deContent.equals("RESULT=SUCCESS")) {
                           
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                        logger.error(e.getMessage());
                    } catch (Exception e) {
                        logger.error(e.getMessage());
                        e.printStackTrace();
                    } finally {
                        if (null != socket) {
                            socket.close();
                        }
    
                    }
    
                }
            }).start();

###  下面是AES加密解密的工具类 ###

import javax.crypto.Cipher;
    import javax.crypto.spec.SecretKeySpec;
    
    /**
     * This program generates a AES key, retrieves its raw bytes, and then
     * reinstantiates a AES key from the key bytes. The reinstantiated key is used
     * to initialize a AES cipher for encryption and decryption.
     */
    public class AES {
    
        private static final String AES = "AES";
    
        private static String CRYPT_KEY = "xinli_zhejiang12";
    
        private static AES	instance;
    
        /**
         * Instantiates a new Aes.
         *
         * @param key the key
         */
        public AES(String key)
        {
            CRYPT_KEY=key;
        }
    
    
        /**
         * 加密
         *
         * @param src the src
         * @param key the key
         * @return byte [ ]
         * @throws Exception the exception
         */
        public  byte[] encrypt(byte[] src, String key) throws Exception {
            Cipher cipher = Cipher.getInstance(AES);
            SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);
            cipher.init(Cipher.ENCRYPT_MODE, securekey);//设置密钥和加密形式
            return cipher.doFinal(src);
        }
    
        /**
         * 加密
         *
         * @param data the data
         * @param key  the key
         * @return byte [ ]
         * @throws Exception
         */
        public final  byte[] encrypt(String data,String key) {
            try {
                return encrypt(data.getBytes(), key);
            } catch (Exception e) {
            }
            return null;
        }
    
        /**
         * 解密
         *
         * @param src the src
         * @param key the key
         * @return byte [ ]
         * @throws Exception the exception
         */
        public static byte[] decrypt(byte[] src, String key)  throws Exception  {
            Cipher cipher = Cipher.getInstance(AES);
            SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);//设置加密Key
            cipher.init(Cipher.DECRYPT_MODE, securekey);//设置密钥和解密形式
            return cipher.doFinal(src);
        }
    
        /**
         * 解密
         *
         * @param data the data
         * @param key  the key
         * @return string
         * @throws Exception
         */
        public final  String decrypt(String data,String key) {
            try {
                return new String(decrypt(hex2byte(data.getBytes()),
                        key));
            } catch (Exception e) {
    
            }
            return null;
        }
    
        /**
         * 二行制转十六进制字符串
         *
         * @param b the b
         * @return string
         */
        public static String byte2hex(byte[] b) {
            String hs = "";
            String stmp = "";
            for (int n = 0; n < b.length; n++) {
                stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
                if (stmp.length() == 1)
                    hs = hs + "0" + stmp;
                else
                    hs = hs + stmp;
            }
            return hs.toUpperCase();
        }
    
        /**
         * Hex 2 byte byte [ ].
         *
         * @param b the b
         * @return the byte [ ]
         */
        public static byte[] hex2byte(byte[] b) {
            if ((b.length % 2) != 0)
                throw new IllegalArgumentException("长度不是偶数");
            byte[] b2 = new byte[b.length / 2];
            for (int n = 0; n < b.length; n += 2) {
                String item = new String(b, n, 2);
                b2[n / 2] = (byte) Integer.parseInt(item, 16);
            }
            return b2;
        }
    
    
        /**
         * 加密
         *
         * @param data the data
         * @return string
         * @throws Exception
         */
        public final  String encrypt(String data) {
            try {
                return byte2hex(encrypt(data.getBytes(), CRYPT_KEY));
            } catch (Exception e) {
            }
            return null;
        }
    
    
        /**
         * Int to byte array byte [ ].
         *
         * @param i the
         * @return the byte [ ]
         */
        public  byte[] intToByteArray(int i) {
            byte[] result = new byte[4];
            //由高位到低位
            result[0] = (byte)((i >> 24) & 0xFF);
            result[1] = (byte)((i >> 16) & 0xFF);
            result[2] = (byte)((i >> 8) & 0xFF);
            result[3] = (byte)(i & 0xFF);
            return result;
        }
    
    
    
    }

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